Probably what is happening is that you are seeing messages from the first trading day, where there hasn't been a daily bar generated yet. So NewDailyBar() hasn't been called and the predayClose values remain 0 or NaN.

In your case, I don't think you need NewDailyBar() so far. Just make dailyFreq public. Then in your NewBar method you can do something like this:

adam01527 (7/18/2016)just wonder how can i print the data in real time?i've tried the FilteredDailyFrequency, still nth print out in live,

Hi Adam,

I'm afraid I didn't understand what you are trying to do here. Can you clarify? You say "in real time", does that mean you are running a live system and want to print out information about bars at certain times? When do you want what to be displayed?

yes, you are correct,im actually calculating the number as below red circle, i need this number every 5 mins in real time,thats why im looking for the previous day close,

as you suggested before, below code works well, but only in simulation mode (CTRL + F5), no output at all during trading hour.....RList<BarData> sym2Daily = OtherSymbols["symbol2"].dailyFreq.Bars;

secondly, i've got a currency exception, it appear when i add SGX traded futures, which valued in USD,i've tried to create a new watchlist folder setting currency in USD, but still not working,the account currency is in HKD,